Region-specific models integrate microscale properties into BOLD signals simulation: the rise of the Hybrid Virtual Brain

Motivation: Virtual brain simulators lack microcircuit region-specificity, critical to extract physiological information at higher scale. Goal(s): We develop a Hybrid Virtual Brain based on region-specific model to enhance BOLD signals simulation. Approach: We simulate whole-brain dynamics by associating the cerebellar mean-field model to the cerebellar cortical regions, and a generic model to the deep cerebellar nuclei and cerebrum. Results: Hybrid Virtual Brain simulations reproduced the rhythmic oscillations and coherence typical of the cerebellar microcircuit and allowed us to correlate electrophysiological and fMRI signals to specific neuronal populations. Impact: By integrating region-specific model technology, the Hybrid Virtual Brain enhances BOLD simulations and captures brain rhythmic oscillations. Its application to neurological diseases will enable the reproduction of altered brain rhythms, fostering the generation of an effective brain digital twin.